The present invention relates to a V-type internal combustion engine with a mechanically driven supercharger, and more particularly, to an engine with a supercharger located essentially between V-shaped cylinder banks of engine, with an intercooler located downstream of supercharger. The intercooler has an intake plenum on the outlet side, and the plenum is connected by intake pipes with the air intakes of the cylinders of both cylinder banks. The supercharger and intercooler form a preassembled module, with the supercharger being located above the intercooler in the installed position, and the intake plenum being located on the top of the intercooler but below the supercharger between V-shaped cylinder banks.
An engine is described in EP 0 529 639 B1 in which a supercharger driven mechanically by the crankshaft is located between the two banks of cylinders of the engine arranged in a V. The supercharger compresses the combustion air drawn in to an increased boost pressure. An intercooler is located above the supercharger, in which the compressed boost air is cooled downstream of the supercharger. The cooled boost air is supplied to the air intakes of the cylinders through the intake pipes.
The two banks of cylinders each have an intake plenum associated with them, each plenum being connected by connecting tubes with the intercooler and supplied with boost air. The two intake plenums run in the lengthwise direction of the cylinder banks above the cylinder heads. The intake pipes to the air intakes of the cylinders branch off from the intake plenums.
This mechanical supercharging system consists of a plurality of individual parts which are assembled when the engine is built and whose functional reliability can only be tested after assembly is complete. As a result, malfunctions of individual parts result in final adjustments that cost both time and money, and prevent completion of the engine.
Another disadvantage is that a plurality of long connecting tubes is necessary to conduct the combustion air between the supercharger, the intercooler, the intake plenums, and the air intakes of the cylinders, resulting in long flow paths with corresponding losses and delayed dynamics. Long response times result, especially during non-steady-state operation of the engine. In addition, the system requires considerable space and is unwieldy to assemble.
Another V-engine is described in U.S. Pat. No. 4,028,892, which likewise teaches a supercharger between the cylinder bands, located above an intercooler, fastened at the bottom of the V between the cylinder banks. After the intake air has flowed through the intercooler, it is fed to an air chamber which communicates with the air intakes of the cylinders. The air chamber is integrated into the engine block and encloses the cylinders of the engine. This design is characterized by a relatively complex design and a high manufacturing cost.